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    <title>Icon Pixel Operations</title>
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          <h4 id="title">Icon Pixel Operations</h4>
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          <p id="shortdesc">Canvas pixel operations on a point icon.</p>
          <div id="docs"><p>Example using an icon to symbolize a point. Click on the icon to select it, and it will be rendered using its negative image.</p>
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          <div id="api-links">Related API documentation: <ul class="inline"><li><a href="../apidoc/ol.Feature.html" title="API documentation for ol.Feature">ol.Feature</a></li>,<li><a href="../apidoc/ol.Map.html" title="API documentation for ol.Map">ol.Map</a></li>,<li><a href="../apidoc/ol.View.html" title="API documentation for ol.View">ol.View</a></li>,<li><a href="../apidoc/ol.geom.Point.html" title="API documentation for ol.geom.Point">ol.geom.Point</a></li>,<li><a href="../apidoc/ol.interaction.Select.html" title="API documentation for ol.interaction.Select">ol.interaction.Select</a></li>,<li><a href="../apidoc/ol.layer.Tile.html" title="API documentation for ol.layer.Tile">ol.layer.Tile</a></li>,<li><a href="../apidoc/ol.layer.Vector.html" title="API documentation for ol.layer.Vector">ol.layer.Vector</a></li>,<li><a href="../apidoc/ol.source.Stamen.html" title="API documentation for ol.source.Stamen">ol.source.Stamen</a></li>,<li><a href="../apidoc/ol.source.Vector.html" title="API documentation for ol.source.Vector">ol.source.Vector</a></li>,<li><a href="../apidoc/ol.style.Icon.html" title="API documentation for ol.style.Icon">ol.style.Icon</a></li>,<li><a href="../apidoc/ol.style.Style.html" title="API documentation for ol.style.Style">ol.style.Style</a></li></ul></div>
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          <textarea class="hidden" name="title">Icon Pixel Operations</textarea>
          <textarea class="hidden" name="description">Canvas pixel operations on a point icon.</textarea>
          <textarea class="hidden" name="js">function createStyle(src, img) {
  return new ol.style.Style({
    image: new ol.style.Icon(/** @type {olx.style.IconOptions} */ ({
      anchor: [0.5, 0.96],
      crossOrigin: &#x27;anonymous&#x27;,
      src: src,
      img: img,
      imgSize: img ? [img.width, img.height] : undefined
    }))
  });
}

var iconFeature &#x3D; new ol.Feature(new ol.geom.Point([0, 0]));
iconFeature.set(&#x27;style&#x27;, createStyle(&#x27;https://openlayers.org/en/v4.4.2/examples/data/icon.png&#x27;, undefined));

var map &#x3D; new ol.Map({
  layers: [
    new ol.layer.Tile({
      source: new ol.source.Stamen({layer: &#x27;watercolor&#x27;})
    }),
    new ol.layer.Vector({
      style: function(feature) {
        return feature.get(&#x27;style&#x27;);
      },
      source: new ol.source.Vector({features: [iconFeature]})
    })
  ],
  target: document.getElementById(&#x27;map&#x27;),
  view: new ol.View({
    center: [0, 0],
    zoom: 3
  })
});

var selectStyle &#x3D; {};
var select &#x3D; new ol.interaction.Select({
  style: function(feature) {
    var image &#x3D; feature.get(&#x27;style&#x27;).getImage().getImage();
    if (!selectStyle[image.src]) {
      var canvas &#x3D; document.createElement(&#x27;canvas&#x27;);
      var context &#x3D; canvas.getContext(&#x27;2d&#x27;);
      canvas.width &#x3D; image.width;
      canvas.height &#x3D; image.height;
      context.drawImage(image, 0, 0, image.width, image.height);
      var imageData &#x3D; context.getImageData(0, 0, canvas.width, canvas.height);
      var data &#x3D; imageData.data;
      for (var i &#x3D; 0, ii &#x3D; data.length; i &lt; ii; i &#x3D; i + (i % 4 &#x3D;&#x3D; 2 ? 2 : 1)) {
        data[i] &#x3D; 255 - data[i];
      }
      context.putImageData(imageData, 0, 0);
      selectStyle[image.src] &#x3D; createStyle(undefined, canvas);
    }
    return selectStyle[image.src];
  }
});
map.addInteraction(select);

map.on(&#x27;pointermove&#x27;, function(evt) {
  map.getTargetElement().style.cursor &#x3D;
      map.hasFeatureAtPixel(evt.pixel) ? &#x27;pointer&#x27; : &#x27;&#x27;;
});
</textarea>
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</textarea>
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        <pre><code id="example-source" class="language-markup">&lt;!DOCTYPE html&gt;
&lt;html&gt;
  &lt;head&gt;
    &lt;title&gt;Icon Pixel Operations&lt;/title&gt;
    &lt;link rel="stylesheet" href="https://openlayers.org/en/v4.4.2/css/ol.css" type="text/css"&gt;
    &lt;!-- The line below is only needed for old environments like Internet Explorer and Android 4.x --&gt;
    &lt;script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"&gt;&lt;/script&gt;
    &lt;script src="https://openlayers.org/en/v4.4.2/build/ol.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
    &lt;div id&#x3D;&quot;map&quot; class&#x3D;&quot;map&quot;&gt;&lt;/div&gt;
    &lt;script&gt;
      function createStyle(src, img) {
        return new ol.style.Style({
          image: new ol.style.Icon(/** @type {olx.style.IconOptions} */ ({
            anchor: [0.5, 0.96],
            crossOrigin: &#x27;anonymous&#x27;,
            src: src,
            img: img,
            imgSize: img ? [img.width, img.height] : undefined
          }))
        });
      }

      var iconFeature &#x3D; new ol.Feature(new ol.geom.Point([0, 0]));
      iconFeature.set(&#x27;style&#x27;, createStyle(&#x27;https://openlayers.org/en/v4.4.2/examples/data/icon.png&#x27;, undefined));

      var map &#x3D; new ol.Map({
        layers: [
          new ol.layer.Tile({
            source: new ol.source.Stamen({layer: &#x27;watercolor&#x27;})
          }),
          new ol.layer.Vector({
            style: function(feature) {
              return feature.get(&#x27;style&#x27;);
            },
            source: new ol.source.Vector({features: [iconFeature]})
          })
        ],
        target: document.getElementById(&#x27;map&#x27;),
        view: new ol.View({
          center: [0, 0],
          zoom: 3
        })
      });

      var selectStyle &#x3D; {};
      var select &#x3D; new ol.interaction.Select({
        style: function(feature) {
          var image &#x3D; feature.get(&#x27;style&#x27;).getImage().getImage();
          if (!selectStyle[image.src]) {
            var canvas &#x3D; document.createElement(&#x27;canvas&#x27;);
            var context &#x3D; canvas.getContext(&#x27;2d&#x27;);
            canvas.width &#x3D; image.width;
            canvas.height &#x3D; image.height;
            context.drawImage(image, 0, 0, image.width, image.height);
            var imageData &#x3D; context.getImageData(0, 0, canvas.width, canvas.height);
            var data &#x3D; imageData.data;
            for (var i &#x3D; 0, ii &#x3D; data.length; i &lt; ii; i &#x3D; i + (i % 4 &#x3D;&#x3D; 2 ? 2 : 1)) {
              data[i] &#x3D; 255 - data[i];
            }
            context.putImageData(imageData, 0, 0);
            selectStyle[image.src] &#x3D; createStyle(undefined, canvas);
          }
          return selectStyle[image.src];
        }
      });
      map.addInteraction(select);

      map.on(&#x27;pointermove&#x27;, function(evt) {
        map.getTargetElement().style.cursor &#x3D;
            map.hasFeatureAtPixel(evt.pixel) ? &#x27;pointer&#x27; : &#x27;&#x27;;
      });
    &lt;/script&gt;
  &lt;/body&gt;
&lt;/html&gt;</code></pre>
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